Skeletal system Flashcards
hematopoiesis
blood cell formation that occurs within bone marrow
compact bone
hard, dense bone tissue that is beneath the outer membrane of a bone. looks smooth and homogeneous
osseous
bone tissue
spongy bone
small needlelike pieces of bone with lots of open space- look like honeycombs and are called trabeculae
long bones
longer than they are wide, mostly compact bone. all limb bones are long except wrist and ankles
short bones
cube shaped, contain spongy bone. includes wrist and ankle bones and kneecap
sesamoid bones
round bones found near joints (e.g. the patella, a small bone that connects muscles inn front of the thigh to the tibia)
flat bones
bones that are thin, flat, and curved. They form the ribs, breastbone, and skull
irregular bones
bones of the vertebrae, hip, and face.
diaphysis
shaft/main section of a long bone
periosteum (hint: osteum think bone)
double-layered connective tissue that covers and nourishes the bone
epiphysis
ends of long bone
articular cartilage
covers the external surface of the epiphyses. Made of hyaline cartilage and decreases friction at joint surfaces
epiphyseal line
remnant of the epiphyseal plate, seen in adult bones
osteogenic/ osteoprogenitor cells
stem cells which create other bone cells, eg osteoblasts
osteoblasts
matrix-synthesising cell that is responsible for bone growth. leads to osteocytes
Osteocytes
mature bone cell that maintains bone matrix
osteoclasts
made from white blood cells, dissolve/reabsorb bone
why do osteoclasts have a spiky/fringy part on their cell?
increases surface area so that the osteoclasts can reabsorb bone more efficiently. Also locks away other parts of the matrix to protect them from being dissolved
mastoid process
a pyramidal bony projection from the posterior section of the temporal bone
zygomatic process
a rough triangular eminence, situated at the angle of separation of the anterior, zygomatic, and orbital surfaces. In front it forms part of the anterior surface
styloid process
a cylindrical, slender, needle-like projection of varying lengths averaging 2 to 3 cm. The styloid process projects from the inferior part of the petrous temporal bone and offers attachment to the stylohyoid ligament and the stylohyoid, stylopharyngeus, and styloglossus muscles
costal
refers to ribs
C1 vertebra
Also known as the atlas, it is missing the spinous process
Intervertebral foramen
gaps in-between vertebrae
condyloid fossa
posterior to occipital condyles, a ditch in bone that leads to canal
“articular/articulation” means
to join
epiphyseal plate
hyaline cartilage that can turn into bone via bone growth (endochondral ossification)
appositional growth
adds another layer of bone growth on existing bone
bone resorption- remodelling of bones
osteoclasts move along bone surface and dig grooves into it. Components of this degradation are recycled into the blood. This process can be kick-started by a deficiency of a certain mineral in the bloodstream.
endochondral ossification
bone develops in childhood through to adolecence. Bone growth occurs through replacement of the hyaline cartilage. Doesn’t include skull and clavicle
intramembraneous ossification
starts in fibrous connective tissue. osteoblasts form from early embryological tissues and initiate bone production
bone deposition
occurs where bone is injured or strength is needed. Osteoblasts create an osteoid gel
bone resorption
osteoclasts dissolve bone via acids and enzymes, digging groves. occurs when body needs the minerals stored within the bone as the components of this degradation are recycled back into the bloodstream.
Compact bone is made of
osteon which are essentially small hollow tubes which provide structural strength. A group of these osteon are known as a bone matrix.
lamellae/ one lamella
Are individual hollow tubes within osteons. collagen fibres run in opposing directions which allows withstanding of torsion.
he hollow centre of the bone matrix (osteon) is known as
the central canal which contains vessels and nerves
perforating canals
connect central canals of osteons on right angles to the central canal.
lacunae
hollow junctions between lamellae that contain octeocytes
canaliculi
thin canals that connect lacunae and central canals
periosteum
lines the outside of bone as a sort of connective tissue
endosteum
lines the bony canals and covers the trabeculae
Wolff’s law
bone can grow or remodel in response to mechanical stress (demands) placed on it.
Fluid containing ions in bone becomes compressed and are sent through canaliculi canals, changing electrical current within bone which sends signal to osteocytes that bones need reformation.
the term fossa
refers to a ditch in the bone
the term foramen
refers to holes
the term process
refers to a protrusion of bone sticking out from main bone.
the term facet
refers to joining point on a bone
